Automatic kelly valve



Dec. 20, 1966 v. D. STONE 3,292,718

AUTOMATIC KELLY VALVE Filed Jan. 29, 1963 s Sheet-Sheet 1 INVENTORI/AQG/L 0. 57 0/VE BY M4 JTTORIVEK Dec. 20, 1966 v. D. STONE 3,292,718

AUTOMATI C KELLY VALVE Filed Jan. 29, 1963 I3 Sheets-Sheet 5 IN VENTORl/lRG/L D. STONE 14770QNEV.

United States Patent 3,292,718 AUTOMATIC KELLY VALVE Virgil D. Stone,Morgan City, La., assignor to Gulf Oil Corporation, Pittsburgh, Pa., acorporation of Pennsylvania Filed Jan. 29, 1963, Ser. No. 254,898 12Claims. (Cl. 175-318) high pressure reservoirs are encountered, and thecooling and lubricating of the drill pipe and bit as they rotate againstthe abrasive rock formations. The satisfactory performance of theseseveral functions requires that the physical properties of the mud beclosely controlled. Ordinarily, the drilling mud comprises a suspensionof natural clays in water, oil, or an emulsion of water and oil. Theaddition of varying amounts of mud chemicals or wetting agents isdetermined by the specific requirements regarding viscosity, density,thixotropy, acidity,

gel strength, shear strength and any other properties that might berequired in a particular case. The volume of mud required for thedrilling of a 15,000 foot well would be approximately one to twothousand barrels and might constitute as much as 20 percent of the totaldrilling costs; therefore, any innovation that reduces the expendituremade in maintaining a suitable mud program will be a significantimprovement in rotary drilling practice.

When drilling is in progress, the mud is pumped from a surfacereservoir, calleda mud pit, to a swivel suspended from the draw works ofthe rotary drilling apparatus and downwardly from the swivel through .astring of drill pipe to a rotary "bit at the bottom of the Well-bore.The mud is ejected at high velocity through a number of ports extendingthrough the walls of the bit and is circulated up the annulus betweenthe drill pipe and wall of the wellbore and back to the mud pit forrecirculation. The force rotating the string of drill pipe is providedby a rotary table located on the rig floor. In order that the rotarytable will have a positive grip on the drill string, the upper end ofthe string is provided with a joint of pipe called a kelly, having apolygonal cross-section designed to fit a similarly shaped opening in akelly drive bushingof the rotary table. The kelly, which isapproximately 50 feet long, is connected in the drill string'from theswivel suspended from the draw works and passes through the kellybushing in the rotary table to the upper joint of drill pipe. Each timea joint of pipe is added to the drill string, the mud pumps are shutdown and the lower end of the kelly is lifted above the rig floor anddisconnected from the drill string. The column of mud that was containedin the kelly when circulation was halted then flows onto the rig floorand creates a safety hazard for the drilling crew as well as wasting theexpensive mud. During the drilling of a 15,000 foot Well, the operationis performed approximately five hundred times, with a loss each time ofover one-half barrel of mud and the cost of idle rig time and wastedman-hours while the mud is washed from the rig floor.

It is the object of this invention to provide a kelly valve assemblywhich is internal to the drill string and has no external connections,and which will prevent the loss of drilling mud when the kelly isdisconnected from the drill string. Such an embodiment of this inventionis illustrated in the accompanying drawings.

FIGURE 1 is an elevational view of rotary drilling apparatus, partiallyin cross-section, showing the valve assembly connected between the kellyand the upper joint of drill pipe.

FIGURE 2 is a vertical, cross-sectional view taken along the line 11-11in FIGURE 1 showing the valve in open position.

FIGURE 3 is a vertical, cross-sectional view similar to FIGURE 2 butshowing the valve in closed position.

FIGURE 4 is a transverse, cross-sectional view taken on the line IV-IVof FIGURE 2 with the valve in open position.

FIGURE 5 is a transverse, cross-sectional view taken on the line VV ofFIGURE 3 with the valve in closed position.

FIGURE 6 is an enlarged vertical sectional view of the assembly forconnecting the kelly valve of this invention in the drill string.

FIGURE 1 illustrates a rotary drilling apparatus which comprises acirculatory system for the drilling mud as it is pumped from .a mud pit,not shown in the drawing, through a stand pipe 10 to a rotary hose 12which is con nected to a swivel 14. The mud then passes through theswivel 14 hanging from a hook 16 which is connected to a traveling blockand draw works not shown in the drawing. The bottom of the swivel 14 isjoined to a kelly 18 which passes through a kelly bushing 20 in a rotarytable 22 rotated by a motor and suitable gearing, not shown in thedrawing. Connected to the lower end of the kelly 18 is a kelly valveassembly 24, which is shown in the open position and which is connectedto the upper end of a string of drill pipe 26 in a well-bore 30. Arotary bit 28, connected to the lower end of the string of drill pipe26, has ports through which the mud flows into the wellbore 30 and upthrough the annulus surrounding the drill pipe to the mud pit, notshown, at thesurface.

FIGURES 2 through 6 show in detail the construction of a kelly valveassembly comprising an outer tubrular casing 34 connected by a bushing58 to the bottom of the kelly 18. An inner tubular :pipe 36 'within thecasing 34 extends downwardly from the bushing 58 through the casing 34to a flexible tubular diaphragm 42 of elastic material such as rubber.The top of the diaphragm 42 is joined to the pipe 36 by a diaphragmconnecter 44a. A similar connector 44b joins the bottom of the diaphragm42 to another inner tubular pipe 56. Thus a valve condluit 60 comprisinga pipe 36, a diaphragm 42, and a pipe 56 forms a cylindrical fluidpassage with a diameter preferably substantially equal to the internaldiameter of the kelly 18 and extending through the casing 34.

An annular chamber 38 extending throughout the length of the valveassembly is formed between the casing 34 and the elements forming thevalve conduit 60. The chamber 38 is sealed at the bottom by meanscomprising a ring seal 48 and an annular metal disk 50 which slip overthe pipe 56 and seat against the bottom of the casing '34. A fluid tightseal between the casing 34 and the ring seal 48 is obtained bytightening a threaded collar 46 against the casing 34. A fluid sealalong the surface of the pipe 56 is obtained by a ring 52 which slipsover the pipe 56 and is compressed against the metal plate 50 by a nut54.

The manner of obtaining a fluid sea-l around the edges of the diaphragm42 is illustrated in FIGURE 6 which shows the detailed construction ofthe diaphragm connector 44b similar in design to an ordinary pipe union.The fluid seal is completed by tightening the threaded members 62 and 64to compress the diaphragm against a flange 66 on the end of the pipe 56.

Patented Dec. 20, 1966 The diaphragm 42 is reinforced at both ends by aplurality of rigid rib supports 40 spaced around the circumterence ofthe diaphragm 42 and pivotally mounted on the upper member 62 of thediaphragm connectors 44a and 44b. FIGURE 3 illustrates the extension ofthe supporting ribs 40 along the diaphragm 42 for part of the distancefrom each end, thus leaving the intermediate portion 70 of the diaphragm42 to form a constriction of the valve conduit 60 when the diaphragm 42is collapsed, thereby closing the valve.

The casing 34 forming the outer wall of the valve assembly has a port 32permitting the introduction of air or other gas into the chamber 38.When the gas within the chamber reaches a desired operating pressure,the port 32 is sealed by a suitable one way vaslve indicated byreference number 72.

In operation, when the pumps are circulating mud through the system asillustrated in FIGURE 1, the pressure exerted upon the internal wall ofthe diaphragm 42 is greater than the pressure in the chamber 38. In thiscondition, the valve remains fiully opened as shown in FIGURES 2 and 4,permitting unrestricted flow of drilling mud through the valve conduit60. When it becomes necessary to change the bit 28 or to add a joint ofpipe to the drill string 26, the pumps are shut down and the kelly 18and valve assembly 24 are withdrawn from the well-bore 30 through therotary table 22. Because the valve assembly 24 is free of externalconnec-, tions, it will pass readily through the rotary table 22 and mayremain connected to the kelly 18 while the work of adding a joint ofpipe or changing bits is being performed. While the pumps are shut down,the pressure.

exerted upon the internal wall of the diaphragm 42 by a column of mudsupported in the kelly 18 and rotary hose 12 is less than the gaspressure in the chamber 38. This higher pressure in the chamber exerts aforce which collapses the diaphragm 42 as illustrated in FIGURES 3 and 5and thereby forms a fluid seal to prevent the loss of drilling mindwhile the kelly 18 and the valve assembly 24 are disconnected from thedrill string.

The type of material comprising the diaphragm 42 will depend upon thespecific requirements of a particular use. Rotary drilling mudordinarily contains an appreciable amount of abrasive sand particleswhich do not settle out in the mud pit but remain suspended in the mudand circulate throughout the system. In a preferred form the diaphragm42 illustrated in FIGURES 1 through 6 comprises two concentric rubbertubes, the inner tube being composed of a hard, durable type of rubberthat will Withstand abrasion by the sand particles in the mud, and theouter tube consisting of a pliable type of rubber that is highlyimpervious to the passage of gas. As shown in FIGURES 2 and 3 the hardermaterial of the inner tube contains a number of expansion grooves topermit a positive seal along the constriction when the valve conduit 60is closed.

The foregoing description illustrates the embodiment, as an integral andpermanent part of a rotary drilling apparatus, of a kelly valve assemblythat prevents the loss of drilling mud when the kelly and valve assemblyare disconnected from the drill string and that has no external membersso that the valve assembly will pass freely through the rotary table. aTherefore I claim as my invention:

1. Apparatus for the rotary drilling of wells comprising a drill string,means for rotating the drill string, and pumping means for circulating adrilling mud downwardly through the drill string to the bottom of thewell, said drill string comprising a kelly, drill pipe in the drillstring below the kelly, a drill bit at the lower end of the drillstring, and a valve in the drill string between the kelly and the drillpipe, said valve having a diaphragm therein defining a conduitcommunicating with the kelly and the drill pipe for the circulation ofdrilling mud therethrough, a chamber within the valve surrounding thediaphragm, and a gas within the chamber under a pressure lower than thepressure of mud circulated through the wardly through the well aroundthe drill string, said.

drill string comprising a kelly, drill pipe in the drill string belowthe kelly, a drill bit at the lower end of the dl'lll string, andclosure means in the drill string between the kelly and the drill pipeto prevent the flow of the drilling fluid from the lower end of thekelly when the pumping means for circulating the drilling fluid arestopped, said closure means comprising a tubular casing connected to thelower end of the kelly and the upper end of the dull pipe and having anouter diameter substantially equal to the outer diameter of the drillpipe, a flexible diaphragm extending longitudinally withinthe casing anddefining a fluid passage therethrough, means securing the diaphragmwithin the casing, a totally enclosed chamber between the diaphragm andthe casing, and resilient means within the chamber urging the diaphragmtransversely across the passage whereby upon stopping the pumping meansfor circulating the drilling fluid the passage is closed to 'preventflow therethrough.

3. Apparatus for the rotary drilling of wells comprising a drill string,means for rotating the drill string, and pumping means for circulating adrilling fluid downwardly through the drill string to the bottom of the'well and upwardly through the well around the drill string, said drillstring comprising a kelly, drill pipe in the drill string below thekelly, a drill bit at the lower end of the drill string, and a valve inthe drill string between the kelly and the drill pipe, said valve havinga flexible tubular diaphragm therein defining a conduit communicatingwith the kelly and the drill pipe for the circulation of drilling fluidtherethrough, a chamber within the valve around the sion resistantmaterial, and the outer tube consisting of a pliable imperviousmaterial.

. 5. Apparatus as described in claim 3 in which a plural ity ofvertically spaced expansion grooves extend circuma ferentially aroundthe inner surface of the diaphragm.

6. Apparatus for the rotary drilling of wells comprismg a drill string,means for rotating the drill string, and

pumping mean-s for circulating a drilling fluid downwardly through thedrill string to the bottom of the well and ripwardly through the wellaround the drill string, said drill string comprising a kelly, drillpipe in the drill string below the kelly, a drill bit at the lower endof the drill string,

and a valve in the drill string between the kelly and the drill pipe,sa1d valve comprising a tubular casing joined to the lower end of thekelly and having an outer diameter substantially equal to the outerdiameter of the drill pipe,

2. flexible tubular diaphragm extending longitudinally with sa1ddiaphragm having an outer diameter in the casing,

less than the inner diameter of the casing and thereby defining achamber between the casing and diaphragm, connecting means joining theends of the diaphragm to the 1 inner wall of the casing and providing afluid-tight seal around the chamber, and a gas sealed within the chamberat a pressure lower than the pressure of the drilling fluid circulatedthrough the valve and adapted to constrict the diaphragm and close thevalve when the pumping means for circulating the drilling fluid arestopped.

7. Apparatus according to claim 6 in which the cum necting means at theends of the diaphragm comprises conduit means at each end of the casingadapted to provide a fluid conduit from the ends of the casing to theends of the diaphragm, unions securing the ends of the diaphragm to saidconduit means Within the casing, said unions each having an externallythreaded member engaging said conduit means and an internally threadedmember engaging the externally threaded member and adapted to compressthe ends of the diaphragm between the union members and said conduitmeans.

8. Apparatus according to claim 7 in which a plurality of rigid ribs arepivotally connected to the internally threaded member of the union andextend therefrom longitudinally along the outer surface of the diaphragmto support said diaphragm.

9. Rotary drilling apparatus having a kelly, drill pipe connected belowthe kelly, and pumps to circulate drilling fluid through the kelly andthe drill pipe, a valve at the lower end of the kelly providing aconduit between the kelly and the drill pipe during circulation of thedrilling fluid therethrough and adapted to close the conduit when thepumps are stopped, said valve comprising a tubular casing secured to thelower end of the kelly and having an outer diameter substantially thesame as that of the drill pipe, said conduit extending through saidcasing and defined therein by the combination of an inlet passage in theupper end of the casing and an outlet passage in the lower end of thecasing with a constrictive passage formed by a flexible tubulardiaphragm secured within the casing between the inlet and outletpassages, said diaphragm having an outer diameter smaller than the innerdiameter of the casing, connecting means providing fluid-tight sealsbetween the ends of the diaphragm and the inner wall of the casing toform a totally enclosed chamber between the diaphragm and the casing,and a fluid sealed within the chamber at a pressure lower than thepressure of drilling fluid circulated through the diaphragm and adaptedto constrict the diaphragm and close the conduit therethrough when thepumps are stopped.

10. Rotary drilling apparatus having a kelly, drill pipe connected belowthe kelly, and pumps to circulate drilling fluid through the kelly anddrill pipe, a valve connected to the lower end of the kelly and theupper end of the drill pipe, said valve comprising a tubular casinghaving an outer diameter substantially equal to that of the drill pipeand forming a substantially even outer surface with the kelly and drillpipe, an inlet tube secured within the upper end of the casing, anoutlet tube secured within the lower end of the casing, a flexibletubular diaphragm extending longitudinally within the casing and joinedto the ends of the inlet and outlet tubes thereby defining a fluidconduit communicating with the lower end of the kelly and the upper endof the drill pipe, a chamber around the diaphragm totally enclosedwithin the casing, and a fluid sealed within the chamber under apressure greater than the hydrostatic pressure exerted on the diaphragmby a column of the drilling fluid supported in the drilling apparatusabove the valve but less than the pressure exerted on the diaphragm bythe drilling fluid circulated therethrough by the pumps.

11. A self-acting direct passage valve for connection between a kellyand drill pipe of rotary drilling apparatus, said valve comprising atubular casing having-an outer diameter substantially equal to that ofthe drill pipe and forming an even outer surface between the kelly anddrill pipe, threads at each end of the tubular casing for connection tothe kelly and the drill pipe, a flexible tubular diaphragm extendinglongitudinally within the casing and secured therein by connectingmeans, said flexible tubular diaphragm defining a fluid passagelongitudinally through the valve, a totally enclosed chamber between thediaphragm and the casing, the outer surface of the tubular diaphragmforming at least a portion of the inner wall of the chamber, and a gassealed within the chamber at a pressure greater than the hydrostaticpressure of a drilling fluid contained in said drilling apparatus abovethe valve but less than the pressure of said drilling fluid as it iscirculated through the drilling apparatus.

12. A self-acting valve for connection between a kelly and drill pipe ofrotary drilling apparatus, said valve adapted to respond automaticallyto changes in fluid pressure of a drilling fluid contained in the valveand comprising a tubular outer casing forming a smooth even surfacebetween the kelly and the drill pipe, said casing being threaded at eachend for connection to the kelly and the drill pipe, a tube extendinglongitudinally within the casing and communicating with the kelly andthe drill pipe and having a flexible center portion, the outer diameterof the tube being smaller than the inner diameter of the casing to forma chamber totally enclosed between the tube and the casing, and a gassealed within the chamber, at a pressure adapted to constrict theflexible portion of the tube when circulation of the drilling fluidtherethrough is stopped.

References Cited by the Examiner UNITED STATES PATENTS CHARLES E.OCONNELL, Primary Examiner.

C. D. JOHNSON, R. E. FAVREAU,

A i an Ex m ne

12. A SELF-ACTING VALVE FOR CONNECTION BETWEEN A KELLY AND DRILL PIPE OFROTARY DRILLING APPARATUS, SAID VALVE ADAPTED TO RESPOND AUTOMATICALLYTO CHANGES IN FLUID PRESSURE OF A DRILLING FLUID CONTAINED IN THE VALVEAND COMPRISING A TUBULAR OUTER CASING FORMING A SMOOTH EVEN SURFACEBETWEEN THE KELLY AND THE DRILL PIPE, SAID CASING BEING THREADED AT EACHEND FOR CONNECTION TO THE KELLY AND THE DRILL PIPE, A TUBE EXTENDINGLONGITUDINALLY WITHIN THE CASING AND COMMUNICATING WITH THE KELLY ANDTHE DRILL PIPE AND HAVING A FLEXIBLE CENTER PORTION, THE OUTER DIAMETEROF THE TUBE BEING SMALLER THAN THE INNER DIAMETER OF THE CASING TO FORMA CHAMBER TOTALLY ENCLOSED BETWEEN THE TUBE AND THE CASING, AND A GASSEALED WITHIN THE CHAMBER, AT A PRESSURE ADAPTED TO CONSTRICT THEFLEXIBLE PORTION OF THE TUBE WHEN CIRCULATION OF THE DRILLING FLUIDTHERETHROUGH IS STOPPED.